{
  "abstract": "Elastically accommodated grain-boundary sliding (EAGBS) is a plausible source of upper-mantle seismic attenuation and dispersion, yet classical theory predicts a localized Debye-like peak that is absent or only weakly expressed in dry olivine experiments. Here we test whether microstructural heterogeneity can explain this discrepancy using 2-D finite-element simulations on periodic Voronoi tessellations. We find that irregular grain geometry changes the baseline EAGBS response relative to the regular hexagonal benchmark, but increasing grain-size variance alone produces only modest changes in modulus and peak height, with little spectral broadening. In contrast, a broad distribution of grain-boundary viscosities progressively suppresses and broadens the Debye-like loss peak into a weak background spanning a wide frequency interval. This broadening arises from the superposition of many localized relaxation processes with distinct characteristic timescales and motivates a reduced-order 0-D description of the aggregate response. These results suggest that the absence of a pronounced EAGBS peak in dry olivine does not necessarily imply the absence of EAGBS mechanism itself. If grain boundaries sample a sufficiently broad viscosity distribution, the macroscopic EAGBS contribution may appear experimentally only as part of a broad attenuation background, while still remaining relevant for upper-mantle seismic attenuation and velocity dispersion.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Journal reference: J. Geophys. Res.: Solid Earth 131 (2026), e2026JB034881",
  "arxiv": "2606.12090",
  "author_total": 2,
  "authors": [
    {
      "name": "Zhengxuan Li"
    },
    {
      "name": "John F. Rudge"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8kecr5d328w62.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2606.12090",
  "fulltext_url": null,
  "id": "8kecr5d328w62",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2606.12090",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "cond-mat.mtrl-sci"
    ],
    [
      "arxiv",
      "physics.comp-ph"
    ],
    [
      "arxiv",
      "physics.geo-ph"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2606.12090",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-08",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/8kecr5d328w62.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:30:52Z",
      "native_id": "2606.12090",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2606.12090"
    }
  ],
  "subjects": [
    {
      "field": "earth",
      "origin": "arxiv:physics.geo-ph",
      "subfield": "geophysics"
    },
    {
      "field": "physics",
      "origin": "arxiv:physics.comp-ph",
      "subfield": "computational"
    },
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Effects of microstructural heterogeneity on the macroscopic spectrum of elastically accommodated grain-boundary sliding",
  "title_text": "Effects of microstructural heterogeneity on the macroscopic spectrum of elastically accommodated grain-boundary sliding",
  "type": "preprint",
  "updated_at": "2026-10-30T12:33:41Z",
  "url": "https://research.draconitic.com/paper/8kecr5d328w62",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1029/2026jb034881",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}